Institute of Slush Hydrogen

 Institute of Slush Hydrogen (ISH) focuses on the research of thermo-fluid phenomena of cryogenic multi-phase flow such as slush flow, boiling flow, and cavitation flow, and on their applications to advanced cryogenic equipment.
 Slush hydrogen contains solid hydrogen particles with the particle size of about 1 mm in liquid hydrogen. It provides an attractive means for energy transportation and storage as functional thermal fluid with superior characteristics due to the high density and latent heat of fusion of the solid particles. In the case of a mass solid fraction of 50 wt.%, slush hydrogen at the temperature of 14 K features a 15% greater density, and an 18% increase in refrigerant heat capacity.
 ISH has originally proposed

the high-efficiency hydrogen energy system using slush hydrogen

taking advantage of the synergetic effect of simultaneous transportation and storage of hydrogen fuel and electrical power, and been engaged in research and development work to put it to practical use.

What's New

  • 1 Oct. 2021
    The pages of "Densimeter and mass flow rate meter for slush hydrogen", "Pool boiling heat transfer to slush hydrogen and slush nitrogen" and "Two-phase boiling nitrogen flow and heat transfer" were revised in the home page "Institute of Slush Hydrogen".
  • 8-10 Dec. 2020
    Dr. Ohira gave the poster exhibition as a fellow of CSSJ on “Practical research and its results of the high-efficiency hydrogen energy system using slush hydrogen” at CSSJ Conference.
  • 15 Sep. 2019
    The interview report on 19 Aug. was published in the monthly magazine "Yano E plus, No. 138" of Yano Research Institute Ltd.
  • 19 Aug. 2019
    Yano Research Institute Ltd. interviewed us to get the information about our research work of cryogenic refrigerator.
    The content of interview: Our experimental verification of the world's first hydrogen liquefaction by magnetic refrigeration, and our research and development work of the high-efficiency hydrogen energy system using slush hydrogen.
  • 9 Apr. 2019
    Dr. Ohira gave the lecture on “Flow and heat transfer characteristics of slush nitrogen and slush hydrogen, and their applications to energy systems” at the 1st technical seminar 2019 of Institute of Cryogenic Engineering promoted by Cryogenics and Superconductivity Society of Japan.
  • 15 Nov. 2018
    Dr. Ohira gave the lecture on “The forefront research of flow and heat transfer characteristics of cryogenic multiphase flow, and the trend of hydrogen energy utilization” at Nikko technical seminar 2018 "Optimization technology of cryogenic fluid instrumentation and control" promoted by Japan Industrial Publishing Co., LTD.
  • 28 Feb. 2018
    Web site "Pressure Drop Reduction and Heat Transfer Deterioration of Slush Nitrogen" was open in Japanese and English.
    URL; https://slush-ish-nitro.com/ , https://slush-ish-nitro-english.com/
  • 5 Jan. 2018
    Web site "The World's First Hydrogen Liquefaction by Magnetic Refrigeration" was open in Japanese and English.
    URL; https://slush-ish-mag.com/ , https://slush-ish-mag-english.com/
  • 25 Sep. 2017
    Home page "Institute of Slush Hydrogen" was open in English.
    URL; https://slush-ish-english.com/
  • 14 Aug. 2017
    Home page "Institute of Slush Hydrogen" was open in Japanese.
    URL; https://slush-ish.com/
  • 19 Jun. 2017
    Dr. Ohira attended “JAXA-Tokyo Univ. collaborative research meeting on rocket propellant and reactive thermal flow”.
  • 29 May 2017
    Dr. Ohira attended as an expert of liquid hydrogen technology "Meeting on safety standards for high-pressure hydrogen gas pressurized by a liquid hydroge pump" and "Working group for leakage experiments and numerical simulations of high-pressure liquid hydrogen".
  • 22 May 2017
    Dr. Ohira gave the presentation on “Pressure drop and heat transfer characteristics of boiling nitrogen in horizontal inverted triangular pipe flow” at CSSJ Conference.
  • 21 Apr. 2017
    Dr. Ohira gave the invited lecture on "Flow and heat transfer study of cryogenic multiphase flow in the development of cryogenic equipment" at Tohoku and Hokkaido Branch Conference of CSSJ.
  • 1 Apr. 2017
    Article on "Development of a high-efficiency hydrogen storage system using liquid and slush hydrogen" was published in Chemical Engineering Vol. 62 (2017) No, 4, 19-26. (in Japanese)
  • Jan. 2017
    Original research paper on "Pressure-drop reduction and heat-transfer deterioration of slush nitrogen in triangular and circular pipe flows" was published in Cryogenics Vol. 81 (2017) No. 1, 60-75.
  • 31 Oct. and 1 Dec. 2016
    Dr. Ohira attended as an expert of liquid hydrogen technology "Meeting on safety standards for high-pressure hydrogen gas pressurized by a liquid hydroge pump" and "Working group for leakage experiments and numerical simulations of high-pressure liquid hydrogen" (contracted-out from NEDO to JIMGA).
  • 1 Jun. 2016
    Dr. Ohira gave the presentation on “Pressure drop of vapor-liquid two-phase nitrogen flow in an unheated horizontal circular pipe” at CSSJ Conference.
  • 31 May 2016
    Cryogenics and Superconductivity Society of Japan (CSSJ) awarded the certificate of Fellow to Dr. Ohira.
  • May 2016
    Institute of Slush Hydrogen (ISH) was established.